Abstract

Polymericmicelles are frequently used to transport and deliver drugs throughout the body because they protect against degradation. Research on functional polymericmicelles for biomedical applications has generally shown that micelles have beneficial properties, such as specific functionality, enhanced specific tumor targeting, and stabilized nanostructures. The particular aim of this study was to synthesize and characterize multifunctional polymericmicelles for use in controlled drug delivery systems and biomedical imaging. In this study, a theranostic agent, doxorubicin/superparamagnetic iron oxide (SPIO)-encapsulated Pluronic F127 (F127) micelles, was developed for dual chemotherapy/magnetic resonance imaging (MRI) purposes, and the structure and composition of the micellar SPIO were characterized by transmission electron microscopy and magnetic measurements. Our results revealed that the micellar SPIO with a diameter of around 100 nm led to a significant advantage in terms of relaxation as compared with a commercial SPIO contrast agent (Resovist®) without cell toxicity. After doxorubicin encapsulation, a dose-dependent darkening of MRimages was observed and HeLa cells were killed by this theranostic micelle. These findings demonstrate that F127 micelles containing chemotherapeutic agents and SPIO could be used as a multifunctional nanocarrier for cancer treatment and imaging.

Received 01 November 2009Accepted 03 December 2009Published online 10 May 2010

Acknowledgments:

This research was supported by grants from the Ministry of Education of the Republic of China under the ATU plan and the National Science Council of the Republic of China (Grant No. NSC 98-2113-M-005-007-MY2). We are grateful to Dr. Jong-Kai Hsiao for his technical support in the use of the clinical 1.5-T MRI system.